Simon Singh, a journalist who wrote a book dismissing homeopathy, told BBC Radio 4's Today programme: "When you look at all the data, when you talk to the editors of the best medical journals, when you talk to the Chief Medical Officer, if you looked at the report from the Commons Select Committee, homeopathy does not work, I'm afraid.

"You will never find a homeopathic drug doping scandal in athletics because all the athletes will get is a sugar rush.

"Because the NHS funds it, it gives it undue credibility. These pills typically have nothing in them whatsoever but you will find charities who will send homeopaths to west Africa to treat Ebola, to south Africa to treat malaria."

Dr Peter Fisher, director of research at the Royal London Hospital for Integrated Medicine, denied homeopathic medicine only had a placebo effect.

"There have been a number of studies - what they call comparative effectiveness studies, in other words you compare GPs who integrate homeopathy in their practice with GPs who do not ... and they are unanimous. All of them show you get better outcomes with homeopathy."